FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person * ROSENBERG GRAHAM LAWRENCE   2. Issuer Name and Ticker or Trading Symbol MDC PARTNERS INC [MDCA] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Managing Director (Last) (First) (Middle) C/O MDC PARTNERS INC., 45 HAZELTON AVENUE 3. Date of Earliest Transaction (Month/Day/Year) 03/13/2006 (Street) TORONTO, A6 M5R 2E3 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Class A Subordinate Voting Shares               4,000 I Owned by spouse Financial Performance-Based Restricted Stock Units (Class A) (1)               35,000 D   Class A Subordinate Voting Shares 03/13/2006   M   65,000 A $ 5 (2) 100,000 D   Class A Subordinate Voting Shares 03/13/2006   D   32,696 D $ 9.94 (2) 67,304 D   Class A Subordinate Voting Shares 03/14/2006   M   26,000 A $ 5.4 (2) 93,304 D   Class A Subordinate Voting Shares 03/14/2006   D   26,000 D $ 9.53 (2) 67,304 D

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Stock Appreciation Rights (3)

$ 5 (2)

03/13/2006

M

65,000

01/22/2004

01/22/2007

Class A Subordinate Voting Shares

65,000

$ 0

0

D

Stock Options (4)

$ 5.4 (2)

03/14/2006

M

26,000

10/09/2002

10/09/2007

Class A Subordinate Voting Shares

26,000

$ 0

13,000

D

Stock Appreciation Rights (3)

$ 9.71 (2)

07/30/2004

07/30/2007

Class A Subordinate Voting Shares

13,333

13,333

D

Stock Options (5)

$ 8.4 (2)

07/31/2003

04/09/2012

Class A Subordinate Voting Shares

47,625

47,625

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
ROSENBERG GRAHAM LAWRENCE C/O MDC PARTNERS INC. 45 HAZELTON AVENUE TORONTO, A6 M5R 2E3			Managing Director

Signatures

Graham L. Rosenberg		03/16/2006
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	A portion of the Financial Performance-Based Restricted Stock Units (Class A Shares) of the Issuer may vest in each of 2007, 2008 and / or 2009 if the Issuer achieves specified performance targets in 2006 - 2008, and is dependent on continued employment. Such financial targets are set forth in a "Financial Performance-Based Restricted Stck Unit Agreement", a form of which was filed by the Issuer as an exhibit to a Form 8-K filed with the SEC on March 2, 2006.
(2)	Canadian dollars.
(3)	Stock Appreciation Rights (previously granted on January 22, 2003 or on July 30, 2003) vest 1/3 on each anniversary of the grant date, expire four years from the grant date, and are settled in cash or in stock, at the option of the Issuer.
(4)	Stock Options (previously granted on October 9, 2002) vest 1/5 on grant and 1/5 on each anniversary of the grant date, expiring five years from the grant date.
(5)	Stock Options (previously granted on July 31, 2003) are deemed to have fully vested on the grant date.

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